Technical Abstract:
Breeding perennial forage, turf, and biofuel crops is a slow process, requiring multiple years to complete each cycle or generation of selection. This is exacerbated when the principal selection criterion is a complex trait of huge economic value, such as turf quality, forage yield, or biomass yield, that must be measured under realistic field conditions that include competition, multiple sites, and multiple years (ages of stand). Adding juvenility and vernalization requirements, which compound this problem for many species, results in cycle times that often exceed five years. Recent advances in DNA sequencing technologies have created opportunities to apply genomic selection technologies to a small number of economically important perennial crops. Genomic selection offers two distinct advantages to perennial forage, turf, and biofuel crops: (1) it creates a ready mechanism to conduct meaningful selection among plants within families for traits that cannot be effectively measured on a single-plant basis (e.g. turf quality, forage yield, and biomass yield under competitive conditions) and (2) it offers an opportunity to drastically reduce the average time required to complete a cycle of selection. Genomic breeding values (GEBV) are computed as the sum of all single-nucleotide polymorphic marker effects, capturing as much variation as possible for the relevant quantitative trait locus. The genetic correlation between GEBV and phenotype, often termed the accuracy of GEBV estimation, is one of the critical keys to the success and efficiency of genomic selection. Early estimates suggest that accuracies of 0.3 to 0.5 could result in doubling of selection gains for perennial grasses and legumes.